Genesis-Plus-GX/source/sound/ym2612.c

/***********************************************************
 *                                                         *
 * YM2612.C : YM2612 emulator                              *
 *                                                         *
 * Almost constantes are taken from the MAME core          *
 *                                                         *
 * This source is a part of Gens project                   *
 * Written by St<EFBFBD>phane Dallongeville (gens@consolemul.com) *
 * Copyright (c) 2002 by St<EFBFBD>phane Dallongeville            *
 *                                                         *
 ***********************************************************/

#include <stdio.h>
#include <math.h>
#include "shared.h"

/********************************************
 *            Partie d<EFBFBD>finition             *
 ********************************************/

#define YM_DEBUG_LEVEL 0

#ifndef PI
#define PI 3.14159265358979323846
#endif

#define ATTACK    0
#define DECAY     1
#define SUBSTAIN  2
#define RELEASE   3

// SIN_LBITS <= 16
// LFO_HBITS <= 16
// (SIN_LBITS + SIN_HBITS) <= 26
// (ENV_LBITS + ENV_HBITS) <= 28
// (LFO_LBITS + LFO_HBITS) <= 28

#define SIN_HBITS      12                // Sinus phase counter int part
#define SIN_LBITS      (26 - SIN_HBITS)          // Sinus phase counter float part (best setting)

#if (SIN_LBITS > 16)
#define SIN_LBITS      16                // Can't be greater than 16 bits
#endif

#define ENV_HBITS      12                // Env phase counter int part
#define ENV_LBITS      (28 - ENV_HBITS)          // Env phase counter float part (best setting)

#define LFO_HBITS      10                // LFO phase counter int part
#define LFO_LBITS      (28 - LFO_HBITS)          // LFO phase counter float part (best setting)

#define SIN_LENGHT     (1 << SIN_HBITS)
#define ENV_LENGHT     (1 << ENV_HBITS)
#define LFO_LENGHT     (1 << LFO_HBITS)

#define TL_LENGHT      (ENV_LENGHT * 3)          // Env + TL scaling + LFO

#define SIN_MASK       (SIN_LENGHT - 1)
#define ENV_MASK       (ENV_LENGHT - 1)
#define LFO_MASK       (LFO_LENGHT - 1)

#define ENV_STEP       (96.0 / ENV_LENGHT)        // ENV_MAX = 96 dB

#define ENV_ATTACK     ((ENV_LENGHT * 0) << ENV_LBITS)
#define ENV_DECAY      ((ENV_LENGHT * 1) << ENV_LBITS)
#define ENV_END        ((ENV_LENGHT * 2) << ENV_LBITS)

#define MAX_OUT_BITS   (SIN_HBITS + SIN_LBITS + 2)    // Modulation = -4 <--> +4
#define MAX_OUT        ((1 << MAX_OUT_BITS) - 1)

//Just for tests stuff...
//
//#define COEF_MOD       0.5
//#define MAX_OUT        ((int) (((1 << MAX_OUT_BITS) - 1) * COEF_MOD))

#define OUT_BITS       (OUTPUT_BITS - 2)
#define OUT_SHIFT      (MAX_OUT_BITS - OUT_BITS)
#define LIMIT_CH_OUT   ((int) (((1 << OUT_BITS) * 1.5) - 1))

#define PG_CUT_OFF     ((int) (78.0 / ENV_STEP))
#define ENV_CUT_OFF    ((int) (68.0 / ENV_STEP))

#define AR_RATE        399128
#define DR_RATE        5514396

//#define AR_RATE        426136
//#define DR_RATE        (AR_RATE * 12)

#define LFO_FMS_LBITS  9  // FIXED (LFO_FMS_BASE gives somethink as 1)
#define LFO_FMS_BASE   ((int) (0.05946309436 * 0.0338 * (double) (1 << LFO_FMS_LBITS)))

#define S0             0  // Stupid typo of the YM2612
#define S1             2
#define S2             1
#define S3             3


void YM2612_Timers_Update(int length);
void YM2612_Special_Update ();

// used for foward...
void Update_Chan_Algo0(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo1(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo2(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo3(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo4(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo5(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo6(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo7(channel_ *CH, int **buf, int lenght);

void Update_Chan_Algo0_LFO(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo1_LFO(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo2_LFO(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo3_LFO(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo4_LFO(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo5_LFO(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo6_LFO(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo7_LFO(channel_ *CH, int **buf, int lenght);

void Update_Chan_Algo0_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo1_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo2_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo3_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo4_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo5_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo6_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo7_Int(channel_ *CH, int **buf, int lenght);

void Update_Chan_Algo0_LFO_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo1_LFO_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo2_LFO_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo3_LFO_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo4_LFO_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo5_LFO_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo6_LFO_Int(channel_ *CH, int **buf, int lenght);
void Update_Chan_Algo7_LFO_Int(channel_ *CH, int **buf, int lenght);

// used for foward...
void Env_Attack_Next(slot_ *SL);
void Env_Decay_Next(slot_ *SL);
void Env_Substain_Next(slot_ *SL);
void Env_Release_Next(slot_ *SL);
void Env_NULL_Next(slot_ *SL);

/********************************************
 *            Partie variables              *
 ********************************************/

struct ym2612__ YM2612;

int *SIN_TAB[SIN_LENGHT];          // SINUS TABLE (pointer on TL TABLE)
int TL_TAB[TL_LENGHT * 2];          // TOTAL LEVEL TABLE (positif and minus)
unsigned int ENV_TAB[2 * ENV_LENGHT + 8];  // ENV CURVE TABLE (attack & decay)

//unsigned int ATTACK_TO_DECAY[ENV_LENGHT];  // Conversion from attack to decay phase
unsigned int DECAY_TO_ATTACK[ENV_LENGHT];  // Conversion from decay to attack phase

unsigned int FINC_TAB[2048];        // Frequency step table

unsigned int AR_TAB[128];          // Attack rate table
unsigned int DR_TAB[96];          // Decay rate table
unsigned int DT_TAB[8][32];          // Detune table
unsigned int SL_TAB[16];          // Substain level table
unsigned int NULL_RATE[32];          // Table for NULL rate

int LFO_ENV_TAB[LFO_LENGHT];        // LFO AMS TABLE (adjusted for 11.8 dB)
int LFO_FREQ_TAB[LFO_LENGHT];        // LFO FMS TABLE
int LFO_ENV_UP[MAX_UPDATE_LENGHT];      // Temporary calculated LFO AMS (adjusted for 11.8 dB)
int LFO_FREQ_UP[MAX_UPDATE_LENGHT];      // Temporary calculated LFO FMS

int INTER_TAB[MAX_UPDATE_LENGHT];      // Interpolation table

int LFO_INC_TAB[8];              // LFO step table

int in0, in1, in2, in3;            // current phase calculation
int en0, en1, en2, en3;            // current enveloppe calculation

static void (*UPDATE_CHAN[8 * 8])(channel_ *CH, int **buf, int lenght) =    // Update Channel functions pointer table
{
  (void *)Update_Chan_Algo0,
  (void *)Update_Chan_Algo1,
  (void *)Update_Chan_Algo2,
  (void *)Update_Chan_Algo3,
  (void *)Update_Chan_Algo4,
  (void *)Update_Chan_Algo5,
  (void *)Update_Chan_Algo6,
  (void *)Update_Chan_Algo7,
  (void *)Update_Chan_Algo0_LFO,
  (void *)Update_Chan_Algo1_LFO,
  (void *)Update_Chan_Algo2_LFO,
  (void *)Update_Chan_Algo3_LFO,
  (void *)Update_Chan_Algo4_LFO,
  (void *)Update_Chan_Algo5_LFO,
  (void *)Update_Chan_Algo6_LFO,
  (void *)Update_Chan_Algo7_LFO,
  (void *)Update_Chan_Algo0_Int,
  (void *)Update_Chan_Algo1_Int,
  (void *)Update_Chan_Algo2_Int,
  (void *)Update_Chan_Algo3_Int,
  (void *)Update_Chan_Algo4_Int,
  (void *)Update_Chan_Algo5_Int,
  (void *)Update_Chan_Algo6_Int,
  (void *)Update_Chan_Algo7_Int,
  (void *)Update_Chan_Algo0_LFO_Int,
  (void *)Update_Chan_Algo1_LFO_Int,
  (void *)Update_Chan_Algo2_LFO_Int,
  (void *)Update_Chan_Algo3_LFO_Int,
  (void *)Update_Chan_Algo4_LFO_Int,
  (void *)Update_Chan_Algo5_LFO_Int,
  (void *)Update_Chan_Algo6_LFO_Int,
  (void *)Update_Chan_Algo7_LFO_Int
};

static void (*ENV_NEXT_EVENT[8])(slot_ *SL) =    // Next Enveloppe phase functions pointer table
{
  (void *)Env_Attack_Next,
  (void *)Env_Decay_Next,
  (void *)Env_Substain_Next,
  (void *)Env_Release_Next,
  (void *)Env_NULL_Next,
  (void *)Env_NULL_Next,
  (void *)Env_NULL_Next,
  (void *)Env_NULL_Next
};

const unsigned int DT_DEF_TAB[4 * 32] =
{
// FD = 0
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

// FD = 1
  0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2,
  2, 3, 3, 3, 4, 4, 4, 5, 5, 6, 6, 7, 8, 8, 8, 8,

// FD = 2
  1, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 4, 4, 4, 5,
  5, 6, 6, 7, 8, 8, 9, 10, 11, 12, 13, 14, 16, 16, 16, 16,

// FD = 3
  2, 2, 2, 2, 2, 3, 3, 3, 4, 4, 4, 5, 5, 6, 6, 7,
  8 , 8, 9, 10, 11, 12, 13, 14, 16, 17, 19, 20, 22, 22, 22, 22
};

const unsigned int FKEY_TAB[16] =
{ 
  0, 0, 0, 0,
  0, 0, 0, 1,
  2, 3, 3, 3,
  3, 3, 3, 3
};

const unsigned int LFO_AMS_TAB[4] =
{
  31, 4, 1, 0
};

const unsigned int LFO_FMS_TAB[8] =
{
  LFO_FMS_BASE * 0, LFO_FMS_BASE * 1,
  LFO_FMS_BASE * 2, LFO_FMS_BASE * 3,
  LFO_FMS_BASE * 4, LFO_FMS_BASE * 6,
  LFO_FMS_BASE * 12, LFO_FMS_BASE * 24
};

int int_cnt;                // Interpolation calculation


#if YM_DEBUG_LEVEL > 0            // Debug
FILE *debug_file = NULL;
#endif

/***********************************************
 *           fonctions calcul param            *
 ***********************************************/


INLINE void CALC_FINC_SL(slot_ *SL, int finc, int kc)
{
  int ksr;
  
  SL->Finc = (finc + SL->DT[kc]) * SL->MUL;

  /* YM2612 Detune Bug (discovered by Nemesis) */
  if (SL->Finc < 0)
  {
    /* Phase overflow (best result with BLOCK = 5) */
    finc = (int)((double)FINC_TAB[0x7FF] / YM2612.Frequence) >> 2;
    SL->Finc = (finc + SL->DT[kc]) * SL->MUL; 
  }
  
  ksr = kc >> SL->KSR_S;  // keycode att<74>nuation

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "FINC = %d  SL->Finc = %d\n", finc, SL->Finc);
#endif

  if (SL->KSR != ksr)      // si le KSR a chang<6E> alors
  {            // les diff<66>rents taux pour l'enveloppe sont mis <20> jour
    SL->KSR = ksr;

    SL->EincA = SL->AR[ksr];
    SL->EincD = SL->DR[ksr];
    SL->EincS = SL->SR[ksr];
    SL->EincR = SL->RR[ksr];

    if (SL->Ecurp == ATTACK) SL->Einc = SL->EincA;
    else if (SL->Ecurp == DECAY) SL->Einc = SL->EincD;
    else if (SL->Ecnt < ENV_END)
    {
      if (SL->Ecurp == SUBSTAIN) SL->Einc = SL->EincS;
      else if (SL->Ecurp == RELEASE) SL->Einc = SL->EincR;
    }

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "KSR = %.4X  EincA = %.8X EincD = %.8X EincS = %.8X EincR = %.8X\n", ksr, SL->EincA, SL->EincD, SL->EincS, SL->EincR);
#endif
  }
}


INLINE void CALC_FINC_CH(channel_ *CH)
{
  int finc, kc;
  
  finc = FINC_TAB[CH->FNUM[0]] >> (7 - CH->FOCT[0]);
  kc = CH->KC[0];

  CALC_FINC_SL(&CH->SLOT[0], finc, kc);
  CALC_FINC_SL(&CH->SLOT[1], finc, kc);
  CALC_FINC_SL(&CH->SLOT[2], finc, kc);
  CALC_FINC_SL(&CH->SLOT[3], finc, kc);
}



/***********************************************
 *             fonctions setting               *
 ***********************************************/


INLINE void KEY_ON(channel_ *CH, int nsl)
{
  slot_ *SL = &(CH->SLOT[nsl]);  // on recup<75>re le bon pointeur de slot
  
  if (SL->Ecurp == RELEASE)    // la touche est-elle rel<65>ch<63>e ?
  {
    SL->Fcnt = 0;

    // Fix Ecco 2 splash sound
    
    SL->Ecnt = (DECAY_TO_ATTACK[ENV_TAB[SL->Ecnt >> ENV_LBITS]] + ENV_ATTACK) & SL->ChgEnM;
    SL->ChgEnM = 0xFFFFFFFF;

//    SL->Ecnt = DECAY_TO_ATTACK[ENV_TAB[SL->Ecnt >> ENV_LBITS]] + ENV_ATTACK;
//    SL->Ecnt = 0;

    SL->Einc = SL->EincA;
    SL->Ecmp = ENV_DECAY;
    SL->Ecurp = ATTACK;
  }
}


INLINE void KEY_OFF(channel_ *CH, int nsl)
{
  slot_ *SL = &(CH->SLOT[nsl]);  // on recup<75>re le bon pointeur de slot
  
  if (SL->Ecurp != RELEASE)    // la touche est-elle appuy<75>e ?
  {
    if (SL->Ecnt < ENV_DECAY)  // attack phase ?
    {
      SL->Ecnt = (ENV_TAB[SL->Ecnt >> ENV_LBITS] << ENV_LBITS) + ENV_DECAY;
    }

    SL->Einc = SL->EincR;
    SL->Ecmp = ENV_END;
    SL->Ecurp = RELEASE;
  }
}


INLINE void CSM_Key_Control()
{
  KEY_ON(&YM2612.CHANNEL[2], 0);
  KEY_ON(&YM2612.CHANNEL[2], 1);
  KEY_ON(&YM2612.CHANNEL[2], 2);
  KEY_ON(&YM2612.CHANNEL[2], 3);

    /* found by Nemesis */
    KEY_OFF(&YM2612.CHANNEL[2], 0);
  KEY_OFF(&YM2612.CHANNEL[2], 1);
  KEY_OFF(&YM2612.CHANNEL[2], 2);
  KEY_OFF(&YM2612.CHANNEL[2], 3);
}


int SLOT_SET(int Adr, unsigned char data)
{
  channel_ *CH;
  slot_ *SL;
  int nch, nsl;

  if ((nch = Adr & 3) == 3) return 1;
  nsl = (Adr >> 2) & 3;

  if (Adr & 0x100) nch += 3;

  CH = &(YM2612.CHANNEL[nch]);
  SL = &(CH->SLOT[nsl]);

  switch(Adr & 0xF0)
  {
    case 0x30:
      if ((SL->MUL = (data & 0x0F))) SL->MUL <<= 1;
      else SL->MUL = 1;

      SL->DT = (int *)DT_TAB[(data >> 4) & 7];

      CH->SLOT[0].Finc = -1;

#if YM_DEBUG_LEVEL > 1
      fprintf(debug_file, "CHANNEL[%d], SLOT[%d] DTMUL = %.2X\n", nch, nsl, data & 0x7F);
#endif
      break;

    case 0x40:
      SL->TL = data & 0x7F;

      // SOR2 do a lot of TL adjustement and this fix R.Shinobi jump sound...
      YM2612_Special_Update();

#if ((ENV_HBITS - 7) < 0)
      SL->TLL = SL->TL >> (7 - ENV_HBITS);
#else
      SL->TLL = SL->TL << (ENV_HBITS - 7);
#endif

#if YM_DEBUG_LEVEL > 1
      fprintf(debug_file, "CHANNEL[%d], SLOT[%d] TL = %.2X\n", nch, nsl, SL->TL);
#endif
      break;

    case 0x50:
      SL->KSR_S = 3 - (data >> 6);

      CH->SLOT[0].Finc = -1;

      if (data &= 0x1F) SL->AR = (int *)&AR_TAB[data << 1];
      else SL->AR = (int *)&NULL_RATE[0];

      SL->EincA = SL->AR[SL->KSR];
      if (SL->Ecurp == ATTACK) SL->Einc = SL->EincA;

#if YM_DEBUG_LEVEL > 1
      fprintf(debug_file, "CHANNEL[%d], SLOT[%d] AR = %.2X  EincA = %.6X\n", nch, nsl, data, SL->EincA);
#endif
      break;

    case 0x60:
      if ((SL->AMSon = (data & 0x80))) SL->AMS = CH->AMS;
      else SL->AMS = 31;

      if (data &= 0x1F) SL->DR = (int *)&DR_TAB[data << 1];
      else SL->DR = (int *)&NULL_RATE[0];

      SL->EincD = SL->DR[SL->KSR];
      if (SL->Ecurp == DECAY) SL->Einc = SL->EincD;

#if YM_DEBUG_LEVEL > 1
      fprintf(debug_file, "CHANNEL[%d], SLOT[%d] AMS = %d  DR = %.2X  EincD = %.6X\n", nch, nsl, SL->AMSon, data, SL->EincD);
#endif
      break;

    case 0x70:
      if (data &= 0x1F) SL->SR = (int *)&DR_TAB[data << 1];
      else SL->SR = (int *)&NULL_RATE[0];

      SL->EincS = SL->SR[SL->KSR];
      if ((SL->Ecurp == SUBSTAIN) && (SL->Ecnt < ENV_END)) SL->Einc = SL->EincS;

#if YM_DEBUG_LEVEL > 1
      fprintf(debug_file, "CHANNEL[%d], SLOT[%d] SR = %.2X  EincS = %.6X\n", nch, nsl, data, SL->EincS);
#endif
      break;

    case 0x80:
      SL->SLL = SL_TAB[data >> 4];

      SL->RR = (int *)&DR_TAB[((data & 0xF) << 2) + 2];

      SL->EincR = SL->RR[SL->KSR];
      if ((SL->Ecurp == RELEASE) && (SL->Ecnt < ENV_END)) SL->Einc = SL->EincR;

#if YM_DEBUG_LEVEL > 1
      fprintf(debug_file, "CHANNEL[%d], SLOT[%d] SL = %.8X\n", nch, nsl, SL->SLL);
      fprintf(debug_file, "CHANNEL[%d], SLOT[%d] RR = %.2X  EincR = %.2X\n", nch, nsl, ((data & 0xF) << 1) | 2, SL->EincR);
#endif
      break;

    case 0x90:
/*
      // SSG-EG envelope shapes :
      //
      // E  At Al H
      //
      // 1  0  0  0  \\\\
      //
      // 1  0  0  1  \___
      //
      // 1  0  1  0  \/\/
      //              ___
      // 1  0  1  1  \
      //
      // 1  1  0  0  ////
      //              ___
      // 1  1  0  1  /
      //
      // 1  1  1  0  /\/\
      //
      // 1  1  1  1  /___
      //
      // E  = SSG-EG enable
      // At = Start negate
      // Al = Altern
      // H  = Hold
*/
      if (data & 0x08) SL->SEG = data & 0x0F;
      else SL->SEG = 0;

#if YM_DEBUG_LEVEL > 1
      fprintf(debug_file, "CHANNEL[%d], SLOT[%d] SSG-EG = %.2X\n", nch, nsl, data);
#endif
      break;
  }

  return 0;
}


int CHANNEL_SET(int Adr, unsigned char data)
{
  channel_ *CH;
  int num;
  
  if ((num = Adr & 3) == 3) return 1;
    
  switch(Adr & 0xFC)
  {
    case 0xA0:
      if (Adr & 0x100) num += 3;
      CH = &(YM2612.CHANNEL[num]);

      YM2612_Special_Update();

      CH->FNUM[0] = (CH->FNUM[0] & 0x700) + data;
      CH->KC[0] = (CH->FOCT[0] << 2) | FKEY_TAB[CH->FNUM[0] >> 7];

      CH->SLOT[0].Finc = -1;

#if YM_DEBUG_LEVEL > 1
      fprintf(debug_file, "CHANNEL[%d] part1 FNUM = %d  KC = %d\n", num, CH->FNUM[0], CH->KC[0]);
#endif
      break;

    case 0xA4:
      if (Adr & 0x100) num += 3;
      CH = &(YM2612.CHANNEL[num]);

      YM2612_Special_Update();

      CH->FNUM[0] = (CH->FNUM[0] & 0x0FF) + ((int) (data & 0x07) << 8);
      CH->FOCT[0] = (data & 0x38) >> 3;
      CH->KC[0] = (CH->FOCT[0] << 2) | FKEY_TAB[CH->FNUM[0] >> 7];

      CH->SLOT[0].Finc = -1;

#if YM_DEBUG_LEVEL > 1
      fprintf(debug_file, "CHANNEL[%d] part2 FNUM = %d  FOCT = %d  KC = %d\n", num, CH->FNUM[0], CH->FOCT[0], CH->KC[0]);
#endif
      break;

    case 0xA8:
      if (Adr < 0x100)
      {
        num++;

        YM2612_Special_Update();

        YM2612.CHANNEL[2].FNUM[num] = (YM2612.CHANNEL[2].FNUM[num] & 0x700) + data;
        YM2612.CHANNEL[2].KC[num] = (YM2612.CHANNEL[2].FOCT[num] << 2) | FKEY_TAB[YM2612.CHANNEL[2].FNUM[num] >> 7];

        YM2612.CHANNEL[2].SLOT[0].Finc = -1;

#if YM_DEBUG_LEVEL > 1
        fprintf(debug_file, "CHANNEL[2] part1 FNUM[%d] = %d  KC[%d] = %d\n", num, YM2612.CHANNEL[2].FNUM[num], num, YM2612.CHANNEL[2].KC[num]);
#endif
      }
      break;

    case 0xAC:
      if (Adr < 0x100)
      {
        num++;

        YM2612_Special_Update();

        YM2612.CHANNEL[2].FNUM[num] = (YM2612.CHANNEL[2].FNUM[num] & 0x0FF) + ((int) (data & 0x07) << 8);
        YM2612.CHANNEL[2].FOCT[num] = (data & 0x38) >> 3;
        YM2612.CHANNEL[2].KC[num] = (YM2612.CHANNEL[2].FOCT[num] << 2) | FKEY_TAB[YM2612.CHANNEL[2].FNUM[num] >> 7];

        YM2612.CHANNEL[2].SLOT[0].Finc = -1;

#if YM_DEBUG_LEVEL > 1
        fprintf(debug_file, "CHANNEL[2] part2 FNUM[%d] = %d  FOCT[%d] = %d  KC[%d] = %d\n", num, YM2612.CHANNEL[2].FNUM[num], num, YM2612.CHANNEL[2].FOCT[num], num, YM2612.CHANNEL[2].KC[num]);
#endif
      }
      break;

    case 0xB0:
      if (Adr & 0x100) num += 3;
      CH = &(YM2612.CHANNEL[num]);

      if (CH->ALGO != (data & 7))
      {
        // Fix VectorMan 2 heli sound (level 1)
        YM2612_Special_Update();

        CH->ALGO = data & 7;
        
        CH->SLOT[0].ChgEnM = 0;
        CH->SLOT[1].ChgEnM = 0;
        CH->SLOT[2].ChgEnM = 0;
        CH->SLOT[3].ChgEnM = 0;
      }

      CH->FB = 9 - ((data >> 3) & 7);                // Real thing ?

//      if (CH->FB = ((data >> 3) & 7)) CH->FB = 9 - CH->FB;    // Thunder force 4 (music stage 8), Gynoug, Aladdin bug sound...
//      else CH->FB = 31;

#if YM_DEBUG_LEVEL > 1
      fprintf(debug_file, "CHANNEL[%d] ALGO = %d  FB = %d\n", num, CH->ALGO, CH->FB);
#endif
      break;

    case 0xB4:
      if (Adr & 0x100) num += 3;
      CH = &(YM2612.CHANNEL[num]);

      YM2612_Special_Update();

      if (data & 0x80) CH->LEFT = 0xFFFFFFFF;
      else CH->LEFT = 0;
      
      if (data & 0x40) CH->RIGHT = 0xFFFFFFFF;
      else CH->RIGHT = 0;
        
      CH->AMS = LFO_AMS_TAB[(data >> 4) & 3];
      CH->FMS = LFO_FMS_TAB[data & 7];

      if (CH->SLOT[0].AMSon) CH->SLOT[0].AMS = CH->AMS;
      else CH->SLOT[0].AMS = 31;
      if (CH->SLOT[1].AMSon) CH->SLOT[1].AMS = CH->AMS;
      else CH->SLOT[1].AMS = 31;
      if (CH->SLOT[2].AMSon) CH->SLOT[2].AMS = CH->AMS;
      else CH->SLOT[2].AMS = 31;
      if (CH->SLOT[3].AMSon) CH->SLOT[3].AMS = CH->AMS;
      else CH->SLOT[3].AMS = 31;

#if YM_DEBUG_LEVEL > 0
      fprintf(debug_file, "CHANNEL[%d] AMS = %d  FMS = %d\n", num, CH->AMS, CH->FMS);
#endif
      break;
  }
  
  return 0;
}


int YM_SET(int Adr, unsigned char data)
{
  channel_ *CH;
  int nch;

  switch(Adr)
  {
    case 0x22:
      if (data & 8)
      {
        // Cool Spot music 1, LFO modified severals time which
        // distord the sound, have to check that on a real genesis...

        YM2612.LFOinc = LFO_INC_TAB[data & 7];

#if YM_DEBUG_LEVEL > 0
        fprintf(debug_file, "\nLFO Enable, LFOinc = %.8X   %d\n", YM2612.LFOinc, data & 7);
#endif
      }
      else
      {
        YM2612.LFOinc = YM2612.LFOcnt = 0;

#if YM_DEBUG_LEVEL > 0
        fprintf(debug_file, "\nLFO Disable\n");
#endif
      }
      break;

    case 0x24:
      YM2612.TimerA = (YM2612.TimerA & 0x003) | (((int) data) << 2);
          YM2612.TimerAL = (1024 - YM2612.TimerA) << 12;

#if YM_DEBUG_LEVEL > 1
          fprintf(debug_file, "Timer A Set = %.8X\n", YM2612.TimerAL);
#endif
      break;

    case 0x25:
      YM2612.TimerA = (YM2612.TimerA & 0x3fc) | (data & 3);
          YM2612.TimerAL = (1024 - YM2612.TimerA) << 12;

#if YM_DEBUG_LEVEL > 1
          fprintf(debug_file, "Timer A Set = %.8X\n", YM2612.TimerAL);
#endif
      break;

    case 0x26:
      YM2612.TimerB = data;
          YM2612.TimerBL = (256 - YM2612.TimerB) << (4 + 12);

#if YM_DEBUG_LEVEL > 1
          fprintf(debug_file, "Timer B Set = %.8X\n", YM2612.TimerBL);
#endif
      break;

    case 0x27:
      // Param<61>tre divers
      // b7 = CSM MODE
      // b6 = 3 slot mode
      // b5 = reset b
      // b4 = reset a
      // b3 = timer enable b
      // b2 = timer enable a
      // b1 = load b
      // b0 = load a

      if ((data ^ YM2612.Mode) & 0xC0)
      {
        // We changed the channel 2 mode, so recalculate phase step
        // This fix the punch sound in Street of Rage 2

        YM2612_Special_Update();

        YM2612.CHANNEL[2].SLOT[0].Finc = -1;    // recalculate phase step
      }

      if ((data & 2) && !(YM2612.Mode & 2)) YM2612.TimerBcnt = YM2612.TimerBL;
      if ((data & 1) && !(YM2612.Mode & 1)) YM2612.TimerAcnt = YM2612.TimerAL;

      YM2612.Status &= (~data >> 4)/* & (data >> 2)*/;  // Reset Status

      YM2612.Mode = data;

#if YM_DEBUG_LEVEL > 0
      fprintf(debug_file, "Mode reg = %.2X\n", data);
#endif
      break;

    case 0x28:
      if ((nch = data & 3) == 3) return 1;

      if (data & 4) nch += 3;
      CH = &(YM2612.CHANNEL[nch]);

      YM2612_Special_Update();

      if (data & 0x10) KEY_ON(CH, S0);  // On appuie sur la touche pour le slot 1
      else KEY_OFF(CH, S0);        // On rel<65>che la touche pour le slot 1
      if (data & 0x20) KEY_ON(CH, S1);  // On appuie sur la touche pour le slot 3
      else KEY_OFF(CH, S1);        // On rel<65>che la touche pour le slot 3
      if (data & 0x40) KEY_ON(CH, S2);  // On appuie sur la touche pour le slot 2
      else KEY_OFF(CH, S2);        // On rel<65>che la touche pour le slot 2
      if (data & 0x80) KEY_ON(CH, S3);  // On appuie sur la touche pour le slot 4
      else KEY_OFF(CH, S3);        // On rel<65>che la touche pour le slot 4

#if YM_DEBUG_LEVEL > 0
      fprintf(debug_file, "CHANNEL[%d]  KEY %.1X\n", nch, ((data & 0xf0) >> 4));
#endif
      break;

    case 0x2A:
      YM2612.DACdata = ((int) data - 0x80) << 7;  // donn<6E>e du DAC
      break;

    case 0x2B:
      if (YM2612.DAC ^ (data & 0x80)) YM2612_Special_Update();

      YM2612.DAC = data & 0x80;  // activation/d<>sactivation du DAC
      break;
  }
  
  return 0;
}



/***********************************************
 *          fonctions de g<EFBFBD>n<EFBFBD>ration            *
 ***********************************************/


void Env_NULL_Next(slot_ *SL)
{
}


void Env_Attack_Next(slot_ *SL)
{
  // Verified with Gynoug even in HQ (explode SFX)
  SL->Ecnt = ENV_DECAY;

  SL->Einc = SL->EincD;
  SL->Ecmp = SL->SLL;
  SL->Ecurp = DECAY;
}


void Env_Decay_Next(slot_ *SL)
{
  // Verified with Gynoug even in HQ (explode SFX)
  SL->Ecnt = SL->SLL;

  SL->Einc = SL->EincS;
  SL->Ecmp = ENV_END;
  SL->Ecurp = SUBSTAIN;
}


void Env_Substain_Next(slot_ *SL)
{
  if (SL->SEG & 8)  // SSG envelope type
  {
    if (SL->SEG & 1)
    {
      SL->Ecnt = ENV_END;
      SL->Einc = 0;
      SL->Ecmp = ENV_END + 1;
    }
    else
    {
      // re KEY ON
      // SL->Fcnt = 0;
      // SL->ChgEnM = 0xFFFFFFFF;
      SL->Ecnt = 0;
      SL->Einc = SL->EincA;
      SL->Ecmp = ENV_DECAY;
      SL->Ecurp = ATTACK;
    }

    SL->SEG ^= (SL->SEG & 2) << 1;
  }
  else
  {
    SL->Ecnt = ENV_END;
    SL->Einc = 0;
    SL->Ecmp = ENV_END + 1;
  }
}


void Env_Release_Next(slot_ *SL)
{
  SL->Ecnt = ENV_END;
  SL->Einc = 0;
  SL->Ecmp = ENV_END + 1;
}


#define GET_CURRENT_PHASE  \
in0 = CH->SLOT[S0].Fcnt;  \
in1 = CH->SLOT[S1].Fcnt;  \
in2 = CH->SLOT[S2].Fcnt;  \
in3 = CH->SLOT[S3].Fcnt;


#define UPDATE_PHASE          \
CH->SLOT[S0].Fcnt += CH->SLOT[S0].Finc;  \
CH->SLOT[S1].Fcnt += CH->SLOT[S1].Finc;  \
CH->SLOT[S2].Fcnt += CH->SLOT[S2].Finc;  \
CH->SLOT[S3].Fcnt += CH->SLOT[S3].Finc;


#define UPDATE_PHASE_LFO                                    \
if ((freq_LFO = (CH->FMS * LFO_FREQ_UP[i]) >> (LFO_HBITS - 1)))                  \
{                                                \
  CH->SLOT[S0].Fcnt += CH->SLOT[S0].Finc + ((CH->SLOT[S0].Finc * freq_LFO) >> LFO_FMS_LBITS);  \
  CH->SLOT[S1].Fcnt += CH->SLOT[S1].Finc + ((CH->SLOT[S1].Finc * freq_LFO) >> LFO_FMS_LBITS);  \
  CH->SLOT[S2].Fcnt += CH->SLOT[S2].Finc + ((CH->SLOT[S2].Finc * freq_LFO) >> LFO_FMS_LBITS);  \
  CH->SLOT[S3].Fcnt += CH->SLOT[S3].Finc + ((CH->SLOT[S3].Finc * freq_LFO) >> LFO_FMS_LBITS);  \
}                                                \
else                                              \
{                                                \
  CH->SLOT[S0].Fcnt += CH->SLOT[S0].Finc;                            \
  CH->SLOT[S1].Fcnt += CH->SLOT[S1].Finc;                            \
  CH->SLOT[S2].Fcnt += CH->SLOT[S2].Finc;                            \
  CH->SLOT[S3].Fcnt += CH->SLOT[S3].Finc;                            \
}


#define GET_CURRENT_ENV                                        \
if (CH->SLOT[S0].SEG & 4)                                      \
{                                                  \
  if ((en0 = ENV_TAB[(CH->SLOT[S0].Ecnt >> ENV_LBITS)] + CH->SLOT[S0].TLL) > ENV_MASK) en0 = 0;  \
  else en0 ^= ENV_MASK;                                      \
}                                                  \
else en0 = ENV_TAB[(CH->SLOT[S0].Ecnt >> ENV_LBITS)] + CH->SLOT[S0].TLL;              \
if (CH->SLOT[S1].SEG & 4)                                      \
{                                                  \
  if ((en1 = ENV_TAB[(CH->SLOT[S1].Ecnt >> ENV_LBITS)] + CH->SLOT[S1].TLL) > ENV_MASK) en1 = 0;  \
  else en1 ^= ENV_MASK;                                      \
}                                                  \
else en1 = ENV_TAB[(CH->SLOT[S1].Ecnt >> ENV_LBITS)] + CH->SLOT[S1].TLL;              \
if (CH->SLOT[S2].SEG & 4)                                      \
{                                                  \
  if ((en2 = ENV_TAB[(CH->SLOT[S2].Ecnt >> ENV_LBITS)] + CH->SLOT[S2].TLL) > ENV_MASK) en2 = 0;  \
  else en2 ^= ENV_MASK;                                      \
}                                                  \
else en2 = ENV_TAB[(CH->SLOT[S2].Ecnt >> ENV_LBITS)] + CH->SLOT[S2].TLL;              \
if (CH->SLOT[S3].SEG & 4)                                      \
{                                                  \
  if ((en3 = ENV_TAB[(CH->SLOT[S3].Ecnt >> ENV_LBITS)] + CH->SLOT[S3].TLL) > ENV_MASK) en3 = 0;  \
  else en3 ^= ENV_MASK;                                      \
}                                                  \
else en3 = ENV_TAB[(CH->SLOT[S3].Ecnt >> ENV_LBITS)] + CH->SLOT[S3].TLL;


#define GET_CURRENT_ENV_LFO                                          \
env_LFO = LFO_ENV_UP[i];                                          \
                                                      \
if (CH->SLOT[S0].SEG & 4)                                          \
{                                                      \
  if ((en0 = ENV_TAB[(CH->SLOT[S0].Ecnt >> ENV_LBITS)] + CH->SLOT[S0].TLL) > ENV_MASK) en0 = 0;      \
  else en0 = (en0 ^ ENV_MASK) + (env_LFO >> CH->SLOT[S0].AMS);                      \
}                                                      \
else en0 = ENV_TAB[(CH->SLOT[S0].Ecnt >> ENV_LBITS)] + CH->SLOT[S0].TLL + (env_LFO >> CH->SLOT[S0].AMS);  \
if (CH->SLOT[S1].SEG & 4)                                          \
{                                                      \
  if ((en1 = ENV_TAB[(CH->SLOT[S1].Ecnt >> ENV_LBITS)] + CH->SLOT[S1].TLL) > ENV_MASK) en1 = 0;      \
  else en1 = (en1 ^ ENV_MASK) + (env_LFO >> CH->SLOT[S1].AMS);                      \
}                                                      \
else en1 = ENV_TAB[(CH->SLOT[S1].Ecnt >> ENV_LBITS)] + CH->SLOT[S1].TLL + (env_LFO >> CH->SLOT[S1].AMS);  \
if (CH->SLOT[S2].SEG & 4)                                          \
{                                                      \
  if ((en2 = ENV_TAB[(CH->SLOT[S2].Ecnt >> ENV_LBITS)] + CH->SLOT[S2].TLL) > ENV_MASK) en2 = 0;      \
  else en2 = (en2 ^ ENV_MASK) + (env_LFO >> CH->SLOT[S2].AMS);                      \
}                                                      \
else en2 = ENV_TAB[(CH->SLOT[S2].Ecnt >> ENV_LBITS)] + CH->SLOT[S2].TLL + (env_LFO >> CH->SLOT[S2].AMS);  \
if (CH->SLOT[S3].SEG & 4)                                          \
{                                                      \
  if ((en3 = ENV_TAB[(CH->SLOT[S3].Ecnt >> ENV_LBITS)] + CH->SLOT[S3].TLL) > ENV_MASK) en3 = 0;      \
  else en3 = (en3 ^ ENV_MASK) + (env_LFO >> CH->SLOT[S3].AMS);                      \
}                                                      \
else en3 = ENV_TAB[(CH->SLOT[S3].Ecnt >> ENV_LBITS)] + CH->SLOT[S3].TLL + (env_LFO >> CH->SLOT[S3].AMS);


#define UPDATE_ENV                            \
if ((CH->SLOT[S0].Ecnt += CH->SLOT[S0].Einc) >= CH->SLOT[S0].Ecmp)    \
  ENV_NEXT_EVENT[CH->SLOT[S0].Ecurp](&(CH->SLOT[S0]));        \
if ((CH->SLOT[S1].Ecnt += CH->SLOT[S1].Einc) >= CH->SLOT[S1].Ecmp)    \
  ENV_NEXT_EVENT[CH->SLOT[S1].Ecurp](&(CH->SLOT[S1]));        \
if ((CH->SLOT[S2].Ecnt += CH->SLOT[S2].Einc) >= CH->SLOT[S2].Ecmp)    \
  ENV_NEXT_EVENT[CH->SLOT[S2].Ecurp](&(CH->SLOT[S2]));        \
if ((CH->SLOT[S3].Ecnt += CH->SLOT[S3].Einc) >= CH->SLOT[S3].Ecmp)    \
  ENV_NEXT_EVENT[CH->SLOT[S3].Ecurp](&(CH->SLOT[S3]));


#define DO_LIMIT                        \
if (CH->OUTd > LIMIT_CH_OUT) CH->OUTd = LIMIT_CH_OUT;      \
else if (CH->OUTd < -LIMIT_CH_OUT) CH->OUTd = -LIMIT_CH_OUT;


#define DO_FEEDBACK0                      \
in0 += CH->S0_OUT[0] >> CH->FB;                  \
CH->S0_OUT[0] = SIN_TAB[(in0 >> SIN_LBITS) & SIN_MASK][en0];


#define DO_FEEDBACK                        \
in0 += (CH->S0_OUT[0] + CH->S0_OUT[1]) >> CH->FB;        \
CH->S0_OUT[1] = CH->S0_OUT[0];                  \
CH->S0_OUT[0] = SIN_TAB[(in0 >> SIN_LBITS) & SIN_MASK][en0];


#define DO_FEEDBACK2                            \
in0 += (CH->S0_OUT[0] + (CH->S0_OUT[0] >> 2) + CH->S0_OUT[1]) >> CH->FB;  \
CH->S0_OUT[1] = CH->S0_OUT[0] >> 2;                      \
CH->S0_OUT[0] = SIN_TAB[(in0 >> SIN_LBITS) & SIN_MASK][en0];
    

#define DO_FEEDBACK3                                  \
in0 += (CH->S0_OUT[0] + CH->S0_OUT[1] + CH->S0_OUT[2] + CH->S0_OUT[3]) >> CH->FB;    \
CH->S0_OUT[3] = CH->S0_OUT[2] >> 1;                            \
CH->S0_OUT[2] = CH->S0_OUT[1] >> 1;                            \
CH->S0_OUT[1] = CH->S0_OUT[0] >> 1;                            \
CH->S0_OUT[0] = SIN_TAB[(in0 >> SIN_LBITS) & SIN_MASK][en0];


#define DO_ALGO_0                              \
DO_FEEDBACK                                  \
in1 += CH->S0_OUT[1];                            \
in2 += SIN_TAB[(in1 >> SIN_LBITS) & SIN_MASK][en1];              \
in3 += SIN_TAB[(in2 >> SIN_LBITS) & SIN_MASK][en2];              \
CH->OUTd = (SIN_TAB[(in3 >> SIN_LBITS) & SIN_MASK][en3]) >> OUT_SHIFT;

#define DO_ALGO_1                              \
DO_FEEDBACK                                  \
in2 += CH->S0_OUT[1] + SIN_TAB[(in1 >> SIN_LBITS) & SIN_MASK][en1];      \
in3 += SIN_TAB[(in2 >> SIN_LBITS) & SIN_MASK][en2];              \
CH->OUTd = (SIN_TAB[(in3 >> SIN_LBITS) & SIN_MASK][en3]) >> OUT_SHIFT;

#define DO_ALGO_2                              \
DO_FEEDBACK                                  \
in2 += SIN_TAB[(in1 >> SIN_LBITS) & SIN_MASK][en1];              \
in3 += CH->S0_OUT[1] + SIN_TAB[(in2 >> SIN_LBITS) & SIN_MASK][en2];      \
CH->OUTd = (SIN_TAB[(in3 >> SIN_LBITS) & SIN_MASK][en3]) >> OUT_SHIFT;

#define DO_ALGO_3                              \
DO_FEEDBACK                                  \
in1 += CH->S0_OUT[1];                            \
in3 += SIN_TAB[(in1 >> SIN_LBITS) & SIN_MASK][en1] + SIN_TAB[(in2 >> SIN_LBITS) & SIN_MASK][en2];  \
CH->OUTd = (SIN_TAB[(in3 >> SIN_LBITS) & SIN_MASK][en3]) >> OUT_SHIFT;

#define DO_ALGO_4                              \
DO_FEEDBACK                                  \
in1 += CH->S0_OUT[1];                            \
in3 += SIN_TAB[(in2 >> SIN_LBITS) & SIN_MASK][en2];              \
CH->OUTd = ((int) SIN_TAB[(in3 >> SIN_LBITS) & SIN_MASK][en3] + (int) SIN_TAB[(in1 >> SIN_LBITS) & SIN_MASK][en1]) >> OUT_SHIFT;  \
DO_LIMIT

#define DO_ALGO_5                              \
DO_FEEDBACK                                  \
in1 += CH->S0_OUT[1];                            \
in2 += CH->S0_OUT[1];                            \
in3 += CH->S0_OUT[1];                            \
CH->OUTd = ((int) SIN_TAB[(in3 >> SIN_LBITS) & SIN_MASK][en3] + (int) SIN_TAB[(in1 >> SIN_LBITS) & SIN_MASK][en1] + (int) SIN_TAB[(in2 >> SIN_LBITS) & SIN_MASK][en2]) >> OUT_SHIFT;  \
DO_LIMIT

#define DO_ALGO_6                              \
DO_FEEDBACK                                  \
in1 += CH->S0_OUT[1];                            \
CH->OUTd = ((int) SIN_TAB[(in3 >> SIN_LBITS) & SIN_MASK][en3] + (int) SIN_TAB[(in1 >> SIN_LBITS) & SIN_MASK][en1] + (int) SIN_TAB[(in2 >> SIN_LBITS) & SIN_MASK][en2]) >> OUT_SHIFT;  \
DO_LIMIT

#define DO_ALGO_7                              \
DO_FEEDBACK                                  \
CH->OUTd = ((int) SIN_TAB[(in3 >> SIN_LBITS) & SIN_MASK][en3] + (int) SIN_TAB[(in1 >> SIN_LBITS) & SIN_MASK][en1] + (int) SIN_TAB[(in2 >> SIN_LBITS) & SIN_MASK][en2] + CH->S0_OUT[1]) >> OUT_SHIFT;  \
DO_LIMIT


#define DO_OUTPUT            \
buf[0][i] += CH->OUTd & CH->LEFT;    \
buf[1][i] += CH->OUTd & CH->RIGHT;


#define DO_OUTPUT_INT0              \
if ((int_cnt += YM2612.Inter_Step) & 0x04000)  \
{                        \
  int_cnt &= 0x3FFF;              \
  buf[0][i] += CH->OUTd & CH->LEFT;      \
  buf[1][i] += CH->OUTd & CH->RIGHT;      \
}                        \
else i--;


#define DO_OUTPUT_INT1              \
CH->Old_OUTd = (CH->OUTd + CH->Old_OUTd) >> 1;  \
if ((int_cnt += YM2612.Inter_Step) & 0x04000)  \
{                        \
  int_cnt &= 0x3FFF;              \
  buf[0][i] += CH->Old_OUTd & CH->LEFT;    \
  buf[1][i] += CH->Old_OUTd & CH->RIGHT;    \
}                        \
else i--;


#define DO_OUTPUT_INT2                \
if ((int_cnt += YM2612.Inter_Step) & 0x04000)    \
{                          \
  int_cnt &= 0x3FFF;                \
  CH->Old_OUTd = (CH->OUTd + CH->Old_OUTd) >> 1;  \
  buf[0][i] += CH->Old_OUTd & CH->LEFT;      \
  buf[1][i] += CH->Old_OUTd & CH->RIGHT;      \
}                          \
else i--;                      \
CH->Old_OUTd = CH->OUTd;


#define DO_OUTPUT_INT              \
if ((int_cnt += YM2612.Inter_Step) & 0x04000)  \
{                        \
  int_cnt &= 0x3FFF;              \
  CH->Old_OUTd = (((int_cnt ^ 0x3FFF) * CH->OUTd) + (int_cnt * CH->Old_OUTd)) >> 14;  \
  buf[0][i] += CH->Old_OUTd & CH->LEFT;    \
  buf[1][i] += CH->Old_OUTd & CH->RIGHT;    \
}                        \
else i--;                    \
CH->Old_OUTd = CH->OUTd;


void Update_Chan_Algo0(channel_ *CH, int **buf, int lenght)
{
  int i;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 0 len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_0
    DO_OUTPUT
  }
}


void Update_Chan_Algo1(channel_ *CH, int **buf, int lenght)
{
  int i;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 1 len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_1
    DO_OUTPUT
  }
}


void Update_Chan_Algo2(channel_ *CH, int **buf, int lenght)
{
  int i;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 2 len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_2
    DO_OUTPUT
  }
}


void Update_Chan_Algo3(channel_ *CH, int **buf, int lenght)
{
  int i;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 3 len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_3
    DO_OUTPUT
  }
}


void Update_Chan_Algo4(channel_ *CH, int **buf, int lenght)
{
  int i;

  if ((CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 4 len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_4
    DO_OUTPUT
  }
}


void Update_Chan_Algo5(channel_ *CH, int **buf, int lenght)
{
  int i;

  if ((CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S2].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 5 len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_5
    DO_OUTPUT
  }
}


void Update_Chan_Algo6(channel_ *CH, int **buf, int lenght)
{
  int i;

  if ((CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S2].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 6 len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_6
    DO_OUTPUT
  }
}


void Update_Chan_Algo7(channel_ *CH, int **buf, int lenght)
{
  int i;

  if ((CH->SLOT[S0].Ecnt == ENV_END) && (CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S2].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 7 len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_7
    DO_OUTPUT
  }
}


void Update_Chan_Algo0_LFO(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 0 LFO len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_0
    DO_OUTPUT
  }
}


void Update_Chan_Algo1_LFO(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 1 LFO len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_1
    DO_OUTPUT
  }
}


void Update_Chan_Algo2_LFO(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 2 LFO len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_2
    DO_OUTPUT
  }
}


void Update_Chan_Algo3_LFO(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 3 LFO len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_3
    DO_OUTPUT
  }
}


void Update_Chan_Algo4_LFO(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if ((CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 4 LFO len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_4
    DO_OUTPUT
  }
}


void Update_Chan_Algo5_LFO(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if ((CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S2].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 5 LFO len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_5
    DO_OUTPUT
  }
}


void Update_Chan_Algo6_LFO(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if ((CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S2].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 6 LFO len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_6
    DO_OUTPUT
  }
}


void Update_Chan_Algo7_LFO(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if ((CH->SLOT[S0].Ecnt == ENV_END) && (CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S2].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 7 LFO len = %d\n\n", lenght);
#endif

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_7
    DO_OUTPUT
  }
}


/******************************************************
 *          Interpolated output                       *
 *****************************************************/


void Update_Chan_Algo0_Int(channel_ *CH, int **buf, int lenght)
{
  int i;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 0 len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_0
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo1_Int(channel_ *CH, int **buf, int lenght)
{
  int i;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 1 len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_1
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo2_Int(channel_ *CH, int **buf, int lenght)
{
  int i;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 2 len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_2
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo3_Int(channel_ *CH, int **buf, int lenght)
{
  int i;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 3 len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_3
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo4_Int(channel_ *CH, int **buf, int lenght)
{
  int i;

  if ((CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 4 len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_4
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo5_Int(channel_ *CH, int **buf, int lenght)
{
  int i;

  if ((CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S2].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 5 len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_5
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo6_Int(channel_ *CH, int **buf, int lenght)
{
  int i;

  if ((CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S2].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 6 len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_6
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo7_Int(channel_ *CH, int **buf, int lenght)
{
  int i;

  if ((CH->SLOT[S0].Ecnt == ENV_END) && (CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S2].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 7 len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE
    GET_CURRENT_ENV
    UPDATE_ENV
    DO_ALGO_7
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo0_LFO_Int(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 0 LFO len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_0
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo1_LFO_Int(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 1 LFO len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_1
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo2_LFO_Int(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 2 LFO len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_2
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo3_LFO_Int(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if (CH->SLOT[S3].Ecnt == ENV_END) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 3 LFO len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_3
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo4_LFO_Int(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if ((CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 4 LFO len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_4
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo5_LFO_Int(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if ((CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S2].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 5 LFO len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_5
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo6_LFO_Int(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if ((CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S2].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 6 LFO len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_6
    DO_OUTPUT_INT
  }
}


void Update_Chan_Algo7_LFO_Int(channel_ *CH, int **buf, int lenght)
{
  int i, env_LFO, freq_LFO;

  if ((CH->SLOT[S0].Ecnt == ENV_END) && (CH->SLOT[S1].Ecnt == ENV_END) && (CH->SLOT[S2].Ecnt == ENV_END) && (CH->SLOT[S3].Ecnt == ENV_END)) return;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nAlgo 7 LFO len = %d\n\n", lenght);
#endif

  int_cnt = YM2612.Inter_Cnt;

  for(i = 0; i < lenght; i++)
  {
    GET_CURRENT_PHASE
    UPDATE_PHASE_LFO
    GET_CURRENT_ENV_LFO
    UPDATE_ENV
    DO_ALGO_7
    DO_OUTPUT_INT
  }
}



/***********************************************
 *            fonctions publiques              *
 ***********************************************/

static long dac_highpass;

// Initialisation de l'<27>mulateur YM2612
int YM2612_Init(int Clock, int Rate, int Interpolation)
{
  int i, j;
  double x;

  if ((Rate == 0) || (Clock == 0)) return 1;

  memset(&YM2612, 0, sizeof(YM2612));

#if YM_DEBUG_LEVEL > 0
  if (debug_file == NULL)
  {
    debug_file = fopen("ym2612.log", "w");
    fprintf(debug_file, "YM2612 logging :\n\n");
  }
#endif

  YM2612.Clock = Clock;
  YM2612.Rate = Rate;

  // 144 = 12 * (prescale * 2) = 12 * 6 * 2
  // prescale set to 6 by default

  YM2612.Frequence = ((double) YM2612.Clock / (double) YM2612.Rate) / 144.0;
  YM2612.TimerBase = (int) (YM2612.Frequence * 4096.0);

  if ((Interpolation) && (YM2612.Frequence > 1.0))
  {
    YM2612.Inter_Step = (unsigned int) ((1.0 / YM2612.Frequence) * (double) (0x4000));
    YM2612.Inter_Cnt = 0;

    // We recalculate rate and frequence after interpolation
      
    YM2612.Rate = YM2612.Clock / 144;
    YM2612.Frequence = 1.0;
  }
  else
  {
    YM2612.Inter_Step = 0x4000;
    YM2612.Inter_Cnt = 0;
  }

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "YM2612 frequence = %g rate = %d  interp step = %.8X\n\n", YM2612.Frequence, YM2612.Rate, YM2612.Inter_Step);
#endif

  // Tableau TL :
  // [0     -  4095] = +output  [4095  - ...] = +output overflow (fill with 0)
  // [12288 - 16383] = -output  [16384 - ...] = -output overflow (fill with 0)

  for(i = 0; i < TL_LENGHT; i++)
  {
    if (i >= PG_CUT_OFF)  // YM2612 cut off sound after 78 dB (14 bits output ?)
    {
      TL_TAB[TL_LENGHT + i] = TL_TAB[i] = 0;
    }
    else
    {
      x = MAX_OUT;                // Max output
      x /= pow(10, (ENV_STEP * i) / 20);      // Decibel -> Voltage

      TL_TAB[i] = (int) x;
      TL_TAB[TL_LENGHT + i] = -TL_TAB[i];
    }

#if YM_DEBUG_LEVEL > 2
    fprintf(debug_file, "TL_TAB[%d] = %.8X    TL_TAB[%d] = %.8X\n", i, TL_TAB[i], TL_LENGHT + i, TL_TAB[TL_LENGHT + i]);
#endif
  }
  
#if YM_DEBUG_LEVEL > 2
  fprintf(debug_file, "\n\n\n\n");
#endif

  // Tableau SIN :
  // SIN_TAB[x][y] = sin(x) * y; 
  // x = phase and y = volume

  SIN_TAB[0] = SIN_TAB[SIN_LENGHT / 2] = &TL_TAB[(int)PG_CUT_OFF];

  for(i = 1; i <= SIN_LENGHT / 4; i++)
  {
    x = sin(2.0 * PI * (double) (i) / (double) (SIN_LENGHT));  // Sinus
    x = 20 * log10(1 / x);                    // convert to dB

    j = (int) (x / ENV_STEP);            // Get TL range

    if (j > PG_CUT_OFF) j = (int) PG_CUT_OFF;

    SIN_TAB[i] = SIN_TAB[(SIN_LENGHT / 2) - i] = &TL_TAB[j];
    SIN_TAB[(SIN_LENGHT / 2) + i] = SIN_TAB[SIN_LENGHT - i] = &TL_TAB[TL_LENGHT + j];

#if YM_DEBUG_LEVEL > 2
    fprintf(debug_file, "SIN[%d][0] = %.8X    SIN[%d][0] = %.8X    SIN[%d][0] = %.8X    SIN[%d][0] = %.8X\n", i, SIN_TAB[i][0], (SIN_LENGHT / 2) - i, SIN_TAB[(SIN_LENGHT / 2) - i][0], (SIN_LENGHT / 2) + i, SIN_TAB[(SIN_LENGHT / 2) + i][0], SIN_LENGHT - i, SIN_TAB[SIN_LENGHT - i][0]);
#endif
  }

#if YM_DEBUG_LEVEL > 2
  fprintf(debug_file, "\n\n\n\n");
#endif

  // Tableau LFO (LFO wav) :

  for(i = 0; i < LFO_LENGHT; i++)
  {
    x = sin(2.0 * PI * (double) (i) / (double) (LFO_LENGHT));  // Sinus
    x += 1.0;
    x /= 2.0;          // positive only
    x *= 11.8 / ENV_STEP;    // ajusted to MAX enveloppe modulation

    LFO_ENV_TAB[i] = (int) x;

    x = sin(2.0 * PI * (double) (i) / (double) (LFO_LENGHT));  // Sinus
    x *= (double) ((1 << (LFO_HBITS - 1)) - 1);

    LFO_FREQ_TAB[i] = (int) x;

#if YM_DEBUG_LEVEL > 2
    fprintf(debug_file, "LFO[%d] = %.8X\n", i, LFO_ENV_TAB[i]);
#endif
  }

#if YM_DEBUG_LEVEL > 2
  fprintf(debug_file, "\n\n\n\n");
#endif

  // Tableau Enveloppe :
  // ENV_TAB[0] -> ENV_TAB[ENV_LENGHT - 1]        = attack curve
  // ENV_TAB[ENV_LENGHT] -> ENV_TAB[2 * ENV_LENGHT - 1]  = decay curve

  for(i = 0; i < ENV_LENGHT; i++)
  {
    // Attack curve (x^8 - music level 2 Vectorman 2)
    x = pow(((double) ((ENV_LENGHT - 1) - i) / (double) (ENV_LENGHT)), 8);
    x *= ENV_LENGHT;

    ENV_TAB[i] = (int) x;

    // Decay curve (just linear)
    x = pow(((double) (i) / (double) (ENV_LENGHT)), 1);
    x *= ENV_LENGHT;

    ENV_TAB[ENV_LENGHT + i] = (int) x;

#if YM_DEBUG_LEVEL > 2
    fprintf(debug_file, "ATTACK[%d] = %d   DECAY[%d] = %d\n", i, ENV_TAB[i], i, ENV_TAB[ENV_LENGHT + i]);
#endif
  }

  ENV_TAB[ENV_END >> ENV_LBITS] = ENV_LENGHT - 1;    // for the stopped state

  // Tableau pour la conversion Attack -> Decay and Decay -> Attack
  
  for(i = 0, j = ENV_LENGHT - 1; i < ENV_LENGHT; i++)
  {
    while (j && (ENV_TAB[j] < (unsigned) i)) j--;

    DECAY_TO_ATTACK[i] = j << ENV_LBITS;
  }

  // Tableau pour le Substain Level
  
  for(i = 0; i < 15; i++)
  {
    x = i * 3;          // 3 and not 6 (Mickey Mania first music for test)
    x /= ENV_STEP;

    j = (int) x;
    j <<= ENV_LBITS;

    SL_TAB[i] = j + ENV_DECAY;
  }

  j = ENV_LENGHT - 1;        // special case : volume off
  j <<= ENV_LBITS;
  SL_TAB[15] = j + ENV_DECAY;

  // Tableau Frequency Step

  for(i = 0; i < 2048; i++)
  {
    x = (double) (i) * YM2612.Frequence;

#if ((SIN_LBITS + SIN_HBITS - (21 - 7)) < 0)
    x /= (double) (1 << ((21 - 7) - SIN_LBITS - SIN_HBITS));
#else
    x *= (double) (1 << (SIN_LBITS + SIN_HBITS - (21 - 7)));
#endif

    x /= 2.0;  // because MUL = value * 2

    FINC_TAB[i] = (unsigned int) x;
  }

  // Tableaux Attack & Decay Rate

  for(i = 0; i < 4; i++)
  {
    AR_TAB[i] = 0;
    DR_TAB[i] = 0;
  }

  for(i = 0; i < 60; i++)
  {
    x = YM2612.Frequence;

    x *= 1.0 + ((i & 3) * 0.25);          // bits 0-1 : x1.00, x1.25, x1.50, x1.75
    x *= (double) (1 << ((i >> 2)));        // bits 2-5 : shift bits (x2^0 - x2^15)
    x *= (double) (ENV_LENGHT << ENV_LBITS);    // on ajuste pour le tableau ENV_TAB

    AR_TAB[i + 4] = (unsigned int) (x / AR_RATE);
    DR_TAB[i + 4] = (unsigned int) (x / DR_RATE);
  }

  for(i = 64; i < 96; i++)
  {
    AR_TAB[i] = AR_TAB[63];
    DR_TAB[i] = DR_TAB[63];

    NULL_RATE[i - 64] = 0;
  }

  // Tableau Detune

  for(i = 0; i < 4; i++)
  {
    for (j = 0; j < 32; j++)
    {
#if ((SIN_LBITS + SIN_HBITS - 21) < 0)
      x = (double) DT_DEF_TAB[(i << 5) + j] * YM2612.Frequence / (double) (1 << (21 - SIN_LBITS - SIN_HBITS));
#else
      x = (double) DT_DEF_TAB[(i << 5) + j] * YM2612.Frequence * (double) (1 << (SIN_LBITS + SIN_HBITS - 21));
#endif

      DT_TAB[i + 0][j] = (int) x;
      DT_TAB[i + 4][j] = (int) -x;
    }
  }

  // Tableau LFO

  j = (YM2612.Rate * YM2612.Inter_Step) / 0x4000;

  LFO_INC_TAB[0] = (unsigned int) (3.98 * (double) (1 << (LFO_HBITS + LFO_LBITS)) / j);
  LFO_INC_TAB[1] = (unsigned int) (5.56 * (double) (1 << (LFO_HBITS + LFO_LBITS)) / j);
  LFO_INC_TAB[2] = (unsigned int) (6.02 * (double) (1 << (LFO_HBITS + LFO_LBITS)) / j);
  LFO_INC_TAB[3] = (unsigned int) (6.37 * (double) (1 << (LFO_HBITS + LFO_LBITS)) / j);
  LFO_INC_TAB[4] = (unsigned int) (6.88 * (double) (1 << (LFO_HBITS + LFO_LBITS)) / j);
  LFO_INC_TAB[5] = (unsigned int) (9.63 * (double) (1 << (LFO_HBITS + LFO_LBITS)) / j);
  LFO_INC_TAB[6] = (unsigned int) (48.1 * (double) (1 << (LFO_HBITS + LFO_LBITS)) / j);
  LFO_INC_TAB[7] = (unsigned int) (72.2 * (double) (1 << (LFO_HBITS + LFO_LBITS)) / j);

  YM2612_Reset();

  return 0;
}

int YM2612_Reset(void)
{
  int i, j;
  
  YM2612.LFOcnt = 0;
  YM2612.TimerA = 0;
  YM2612.TimerAL = 0;
  YM2612.TimerAcnt = 0;
  YM2612.TimerB = 0;
  YM2612.TimerBL = 0;
  YM2612.TimerBcnt = 0;
  YM2612.DAC = 0;
  YM2612.DACdata = 0;
  dac_highpass = 0;

  YM2612.Status = 0;

  YM2612.OPNAadr = 0;
  YM2612.OPNBadr = 0;
  YM2612.Inter_Cnt = 0;

  for(i = 0; i < 6; i++)
  {
    YM2612.CHANNEL[i].Old_OUTd = 0;
    YM2612.CHANNEL[i].OUTd = 0;
    YM2612.CHANNEL[i].LEFT = 0xFFFFFFFF;
    YM2612.CHANNEL[i].RIGHT = 0xFFFFFFFF;
    YM2612.CHANNEL[i].ALGO = 0;;
    YM2612.CHANNEL[i].FB = 31;
    YM2612.CHANNEL[i].FMS = 0;
    YM2612.CHANNEL[i].AMS = 0;

    for(j = 0 ;j < 4 ; j++)
    {
      YM2612.CHANNEL[i].S0_OUT[j] = 0;
      YM2612.CHANNEL[i].FNUM[j] = 0;
      YM2612.CHANNEL[i].FOCT[j] = 0;
      YM2612.CHANNEL[i].KC[j] = 0;

      YM2612.CHANNEL[i].SLOT[j].Fcnt = 0;
      YM2612.CHANNEL[i].SLOT[j].Finc = 0;
      YM2612.CHANNEL[i].SLOT[j].Ecnt = ENV_END;    // Put it at the end of Decay phase...
      YM2612.CHANNEL[i].SLOT[j].Einc = 0;
      YM2612.CHANNEL[i].SLOT[j].Ecmp = 0;
      YM2612.CHANNEL[i].SLOT[j].Ecurp = RELEASE;

      YM2612.CHANNEL[i].SLOT[j].ChgEnM = 0;
    }
  }

  for(i = 0; i < 0x100; i++)
  {
    YM2612.REG[0][i] = -1;
    YM2612.REG[1][i] = -1;
  }

  for(i = 0xB6; i >= 0xB4; i--)
  {
    YM2612_Write(0, (unsigned char) i);
    YM2612_Write(2, (unsigned char) i);
    YM2612_Write(1, 0xC0);
    YM2612_Write(3, 0xC0);
  }

  for(i = 0xB2; i >= 0x22; i--)
  {
    YM2612_Write(0, (unsigned char) i);
    YM2612_Write(2, (unsigned char) i);
    YM2612_Write(1, 0);
    YM2612_Write(3, 0);
  }

  YM2612_Write(0, 0x2A);
  YM2612_Write(1, 0x80);

#if YM_DEBUG_LEVEL > 0
  fprintf(debug_file, "\n\nFinishing reseting YM2612 ...\n\n");
#endif

  return 0;
}


int YM2612_Read(void)
{
/*  static int cnt = 0;

  if (cnt++ == 50)
  {
    cnt = 0;
    return YM2612.Status;
  }
  else return YM2612.Status | 0x80;
*/
  return YM2612.Status;
}


int YM2612_Write(unsigned char adr, unsigned char data)
{
  int d;
  
  //data &= 0xFF;
    adr  &= 0x03;
  
  switch(adr)
  {
    case 0:
      YM2612.OPNAadr = data;
      break;

    case 1:
      // Trivial optimisation
      if (YM2612.OPNAadr == 0x2A)
      {
        YM2612.DACdata = ((int) data - 0x80) << 7;
        YM2612.REG[0][0x2A] = data;
        return 0;
      }

      d = YM2612.OPNAadr & 0xF0;

      if (d >= 0x30)
      {
        if (YM2612.REG[0][YM2612.OPNAadr] == data) return 2;
        YM2612.REG[0][YM2612.OPNAadr] = data;

        if (d < 0xA0)    // SLOT
        {
          SLOT_SET(YM2612.OPNAadr, data);
        }
        else        // CHANNEL
        {
          CHANNEL_SET(YM2612.OPNAadr, data);
        }
      }
      else          // YM2612
      {
        YM2612.REG[0][YM2612.OPNAadr] = data;
        YM_SET(YM2612.OPNAadr, data);
      }
      break;

    case 2:
      YM2612.OPNBadr = data;
      break;

    case 3:
      d = YM2612.OPNBadr & 0xF0;

      if (d >= 0x30)
      {
        if (YM2612.REG[1][YM2612.OPNBadr] == data) return 2;
        YM2612.REG[1][YM2612.OPNBadr] = data;

        if (d < 0xA0)    // SLOT
        {
          SLOT_SET(YM2612.OPNBadr + 0x100, data);
        }
        else        // CHANNEL
        {
          CHANNEL_SET(YM2612.OPNBadr + 0x100, data);
        }
      }
      else return 1;
      break;
  }

  return 0;
}


void YM2612_Update(int **buf, int length)
{
  int i, j, algo_type;

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nStarting generating sound...\n\n");
#endif

  // Mise <20> jour des pas des compteurs-fr<66>quences s'ils ont <20>t<EFBFBD> modifi<66>s

  if (YM2612.CHANNEL[0].SLOT[0].Finc == -1) CALC_FINC_CH(&YM2612.CHANNEL[0]);
  if (YM2612.CHANNEL[1].SLOT[0].Finc == -1) CALC_FINC_CH(&YM2612.CHANNEL[1]);
  if (YM2612.CHANNEL[2].SLOT[0].Finc == -1)
  {
    /*----------------------
        |Mode| Behaviour     |
        |----|---------------|
        | 00 | Normal        |
        | 01 | Special       |
        | 10 | Special + CSM |
        | 11 | Special       |
        ---------------------- */
      if (YM2612.Mode & 0xC0)
    {
      CALC_FINC_SL(&(YM2612.CHANNEL[2].SLOT[S0]), FINC_TAB[YM2612.CHANNEL[2].FNUM[2]] >> (7 - YM2612.CHANNEL[2].FOCT[2]), YM2612.CHANNEL[2].KC[2]);
      CALC_FINC_SL(&(YM2612.CHANNEL[2].SLOT[S1]), FINC_TAB[YM2612.CHANNEL[2].FNUM[3]] >> (7 - YM2612.CHANNEL[2].FOCT[3]), YM2612.CHANNEL[2].KC[3]);
      CALC_FINC_SL(&(YM2612.CHANNEL[2].SLOT[S2]), FINC_TAB[YM2612.CHANNEL[2].FNUM[1]] >> (7 - YM2612.CHANNEL[2].FOCT[1]), YM2612.CHANNEL[2].KC[1]);
      CALC_FINC_SL(&(YM2612.CHANNEL[2].SLOT[S3]), FINC_TAB[YM2612.CHANNEL[2].FNUM[0]] >> (7 - YM2612.CHANNEL[2].FOCT[0]), YM2612.CHANNEL[2].KC[0]);
    }
    else
    {
      CALC_FINC_CH(&YM2612.CHANNEL[2]);
    }
  }
  if (YM2612.CHANNEL[3].SLOT[0].Finc == -1) CALC_FINC_CH(&YM2612.CHANNEL[3]);
  if (YM2612.CHANNEL[4].SLOT[0].Finc == -1) CALC_FINC_CH(&YM2612.CHANNEL[4]);
  if (YM2612.CHANNEL[5].SLOT[0].Finc == -1) CALC_FINC_CH(&YM2612.CHANNEL[5]);

/*
  CALC_FINC_CH(&YM2612.CHANNEL[0]);
  CALC_FINC_CH(&YM2612.CHANNEL[1]);
  if (YM2612.Mode & 0x40)
  {
    CALC_FINC_SL(&(YM2612.CHANNEL[2].SLOT[0]), FINC_TAB[YM2612.CHANNEL[2].FNUM[2]] >> (7 - YM2612.CHANNEL[2].FOCT[2]), YM2612.CHANNEL[2].KC[2]);
    CALC_FINC_SL(&(YM2612.CHANNEL[2].SLOT[1]), FINC_TAB[YM2612.CHANNEL[2].FNUM[3]] >> (7 - YM2612.CHANNEL[2].FOCT[3]), YM2612.CHANNEL[2].KC[3]);
    CALC_FINC_SL(&(YM2612.CHANNEL[2].SLOT[2]), FINC_TAB[YM2612.CHANNEL[2].FNUM[1]] >> (7 - YM2612.CHANNEL[2].FOCT[1]), YM2612.CHANNEL[2].KC[1]);
    CALC_FINC_SL(&(YM2612.CHANNEL[2].SLOT[3]), FINC_TAB[YM2612.CHANNEL[2].FNUM[0]] >> (7 - YM2612.CHANNEL[2].FOCT[0]), YM2612.CHANNEL[2].KC[0]);
  }
  else
  {
    CALC_FINC_CH(&YM2612.CHANNEL[2]);
  }
  CALC_FINC_CH(&YM2612.CHANNEL[3]);
  CALC_FINC_CH(&YM2612.CHANNEL[4]);
  CALC_FINC_CH(&YM2612.CHANNEL[5]);
*/

  if (YM2612.Inter_Step & 0x04000) algo_type = 0;
  else algo_type = 16;

  if (YM2612.LFOinc)
  {
    // Precalcul LFO wav
    
    for(i = 0; i < length; i++)
    {
      j = ((YM2612.LFOcnt += YM2612.LFOinc) >> LFO_LBITS) & LFO_MASK;

      LFO_ENV_UP[i] = LFO_ENV_TAB[j];
      LFO_FREQ_UP[i] = LFO_FREQ_TAB[j];

#if YM_DEBUG_LEVEL > 3
      fprintf(debug_file, "LFO_ENV_UP[%d] = %d   LFO_FREQ_UP[%d] = %d\n", i, LFO_ENV_UP[i], i, LFO_FREQ_UP[i]);
#endif
    }

    algo_type |= 8;
  }

  UPDATE_CHAN[YM2612.CHANNEL[0].ALGO + algo_type](&(YM2612.CHANNEL[0]), buf, length);
  UPDATE_CHAN[YM2612.CHANNEL[1].ALGO + algo_type](&(YM2612.CHANNEL[1]), buf, length);
  UPDATE_CHAN[YM2612.CHANNEL[2].ALGO + algo_type](&(YM2612.CHANNEL[2]), buf, length);
  UPDATE_CHAN[YM2612.CHANNEL[3].ALGO + algo_type](&(YM2612.CHANNEL[3]), buf, length);
  UPDATE_CHAN[YM2612.CHANNEL[4].ALGO + algo_type](&(YM2612.CHANNEL[4]), buf, length);
  if (!(YM2612.DAC)) UPDATE_CHAN[YM2612.CHANNEL[5].ALGO + algo_type](&(YM2612.CHANNEL[5]), buf, length);
  else 
  {
    for(i = 0; i < length; i++)
    {
      buf[0][i] += YM2612.DACdata & YM2612.CHANNEL[5].LEFT;
      buf[1][i] += YM2612.DACdata & YM2612.CHANNEL[5].RIGHT;
    }
  }

  YM2612.Inter_Cnt = int_cnt;

  /* update timers here */
  YM2612_Timers_Update(length);

#if YM_DEBUG_LEVEL > 1
  fprintf(debug_file, "\n\nFinishing generating sound...\n\n");
#endif

}

void YM2612_Timers_Update(int length)
{
  int i;

  i = YM2612.TimerBase * length;

  if (YM2612.Mode & 1)  // Timer A ON ?
  {
    if ((YM2612.TimerAcnt -= i) <= 0)
    {
      YM2612.Status |= (YM2612.Mode & 0x04) >> 2;
      YM2612.TimerAcnt += YM2612.TimerAL;
          /*----------------------
          |Mode| Behaviour     |
          |----|---------------|
          | 00 | Normal        |
          | 01 | Special       |
          | 10 | Special + CSM |
          | 11 | Special       |
          ---------------------- */
          if ((YM2612.Mode & 0xC0) == 0x80) CSM_Key_Control(); // found by Nemesis
    }
  }

  if (YM2612.Mode & 2)  // Timer B ON ?
  {
    if ((YM2612.TimerBcnt -= i) <= 0)
    {
      YM2612.Status |= (YM2612.Mode & 0x08) >> 2;
      YM2612.TimerBcnt += YM2612.TimerBL;
    }
  }
}

void YM2612_Special_Update ()
{}